It was established the strong changes in elements of antioxidation system by the influence of acid stress. The different reaction of varieties in these conditions was discovered. More early ripening varieties were more sensitive to acid stress. The relative indexes of plant antioxidation system conditions were calculated. The relative evaluation of the sensitivity of studied varieties to the acid stress was done by those indexes. We propose to use index of common recovering activity of tissue as a test index for the estimation of different peach varieties to acid stress

We studied elevated CO2 and ozone effects in single and in combination on crown structure of two Betula pendula clones. Shoot ramification, shoot length, number of metamers, leaves and buds were measured at four heights in every tree. Chamber effect was substantial on sylleptic branching and on shoot length and ramification. However these responses differed between the clones. Ozone treatment affected shoot length and caused slight decrease in shoot ramification. Elevated CO2 affected appearance of long shoots in complex manner, but in lower crown positions CO2 caused increased number of long shoots in both clones

The results showed that the hydrogen load had a very significant variation between the two monitoring years. In 1999-00 water year, hydrogen load was 4.72 kmol/ha, while in 2000-01 it was 1.70 kmol/ha. Although the observed pH values of rainwater never got over 7.0, high values around 6.0 were determined in summer moonths. The average equivalent concentrations of measured ions were calculated and an equilibrium between anions and cations was found

Major part of implemented measures was aimed at early artificial forest regeneration and securing plantations, or protection of young forest stands against damage by bark beetles. Only exceptionally there were proposed measures with the aim to increase vitality, stability and improvement of the structure of forest stands by their tending. It was worked out a draft of procedures for forest managers to help them in deciding at which stocking it is necessary to reforest reduced or actual clearings, whether to fell down open stands or to leave them regarding their age, state and expected further development

We studied whether the increased abundance of B. ulmella in 1997 was associated with environmental pollution from an aluminium plant. To clarify this question we selected nine study sites at a distance of 1.4-18 km (control) from the aluminium plant in Central Slovakia. We found a sigifnicant difference in the moth numbers between the third and fourth site even though these sites are distant from each other only about 200 m. Each site was exposed to pollution from different part of the plant complex producing specific emissions of different quantity. This might explain differences in the moth abundance within the polluted area

Research project main aims are coordinating, summarizing and making interpretation from the research results from the region of interest. Further targets are to focus, concentrate and promote research activities of relevant departments of the Faculty of Forestry in this area. Intention of organising institution is to create a material, grouping together research results available from the Ore Mts., forming a basis for results exchange and launching the data as well as for results utilisable in the forest practice in this region

Presented study documents the effects of experimental liming on the forest soils and forest plantations (Norway spruce). Liming was performed in the top part of the Orlicke hory Mts., in the altitude 1100 m. Results documented mutual effects on the forest soil as well as on the newly established Norway spruce plantations. It was evaluated the effect of liming on the soil pH, soil adsorption complex, exchangeable nutrients. Special attention was paid to the nitrogen dynamics and to the plantation growth and nutrition

Significant correlations (p0.05) were found between the concentration of elements in the c needles and the distance of the sites from nitrogen ferilizer factory (NFF): the amounts of C, K, Mg, Zn, and Rb in the c+1 needles were increasing, whereas concentrations of N, P, Al, Mn, Cu, Ni, Sr and Cd were decreasing alongside the transect from NFF. Statistical analyses performed on logarithms and estimation of components of variance by maximum likelihood has shown that the age of the needles and the sites were the most important, while year of sampling was much smaller source of variance. Only a few significant differences were found comparing the amount of elements in Scots pine needles collected in four-year space

We studied the effects of elevated CO2 and elevated temperature on photosynthesis and composition of Scots pine needles during three years of treatments, started in August 1996. CO2 and temperature were elevated day- and year- round in closed-top chambers, which were constructed around naturally regenerated Scots pine trees growing at a nitrogen poor site. Our aim was to study, whether there is photosynthetic acclimation during three years of growth at elevated CO2 and elevated temperature in Scots pine, and whether acclimation response is connected to the aging of the needles

We aim to differentiate the various visible leaf symptoms in the field survey with microscopical methods, and to better know, how the leaf, tissue and cell response differs between injury from ozone, heavy metals (both oxidative stress) and biotic infections